Element 94 | Article about Element 94 by The Free Dictionary Element 94 | Article about Element 94 by The Free Dictionary Related to Element 94: periodic table , plutonium , Element 95 , Element 96 , Element 89 plutonium (plo͞otō`nēəm), radioactive chemical element; symbol Pu; at. no. 94; mass no. of most stable isotope 244; m.p. 641&degC;; b.p. 3,232&degC;; sp. gr. 19.84 at 20&degC;; valence +3, +4, +5, or +6. Plutonium is a silver-gray radioactive metal that has six allotropic forms (see allotropy allotropy [Gr.,=other form]. A chemical element is said to exhibit allotropy when it occurs in two or more forms in the same physical state; the forms are called allotropes. ..... Click the link for more information. ). It is a member of the actinide series actinide series, a series of radioactive metallic elements in Group 3 of the periodic table.

Members of the series are often called actinides, although actinium (at. no. 89) is not always considered a member of the series. ..... Click the link for more information. in Group 3 of the periodic table periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled ..... Click the link for more information. . Plutonium is chemically reactive. It tarnishes in air, taking on a yellow cast when oxidized. It dissolves in hydrochloric, hydriodic, and perchloric acids and reacts with the halogens, carbon, nitrogen, and silicon. Pure plutonium metal may be prepared by reduction of the trifluoride, PuF3, with calcium metal. Sixteen isotopes of plutonium are known. The most stable is plutonium-244 (half-life about 82 million years). By far the most important is plutonium-239 (half-life about 24,000 years), a nuclear fission fuel.

Plutonium-239 is produced in large quantities in nuclear reactors from uranium-238, an abundant but nonfissionable isotope. Uranium-238 absorbs neutrons emitted by the fission of uranium-235; uranium-239 is formed, which emits a beta particle and decays to neptunium-239; the neptunium-239 emits another beta particle, becoming plutonium-239. Once begun, the reaction proceeds spontaneously until the uranium fuel rods in the reactor are converted to a certain uranium-plutonium mixture. The rods are dissolved in acid and the plutonium separated by chemical means, especially by solvent extraction. Plutonium is important for its use in nuclear weapons and nuclear reactors. Plutonium-238 has been used to power scientific equipment in lunar exploration and implanted heart pacemakers (see pacemaker, artificial pacemaker, artificial, device used to stimulate a rhythmic heartbeat by means of electrical impulses. Implanted in the body when the heart's own electrical conduction system (natural pacemaker) does not function normally, the battery-powered device emits impulses that trigger ..... Click the link for more information. ).

Plutonium is an extremely dangerous poison; it collects in the bones and interferes with the production of white blood cells. Plutonium is found naturally in very small quantities in association with uranium ores. However, it was discovered in 1940 at the Univ. of California at Berkeley by Glenn T. Seaborg Seaborg, Glenn Theodore , 1912–99, American chemist, b. Ishpeming, Mich., grad. Univ. of California at Los Angeles, 1934, Ph.D. Univ. of California at Berkeley, 1937. ..... Click the link for more information. , Edwin M. McMillan McMillan, Edwin Mattison, 1907–91, American physicist, b. Redondo Beach, Calif., grad. California Institute of Technology, 1928, Ph.D. Princeton, 1932. On the faculty of the Univ. ..... Click the link for more information. , Joseph W. Kennedy, and Arthur C.

Wahl; using a cyclotron to bombard uranium oxide with deuterons, they produced plutonium-238 ( half-life half-life, measure of the average lifetime of a radioactive substance (see radioactivity) or an unstable subatomic particle. One half-life is the time required for one half of any given quantity of the substance to decay. ..... Click the link for more information. about 87 years). Plutonium, the second transuranium element transuranium elements, in chemistry, radioactive elements with atomic numbers greater than that of uranium (at. no. 92). All the transuranium elements of the actinide series were discovered as synthetic radioactive isotopes at the Univ. ..... Click the link for more information. , was named for Pluto Pluto, in astronomy, a dwarf planet and the first Kuiper belt, or transneptunian, object (see comet) to be discovered (1930) by astronomers. Pluto has an elliptical orbit usually lying beyond that of Neptune. ..... Click the link for more information. , then regarded as the second planet beyond Uranus. Plutonium Pu, an artificial radioactive chemical element with atomic number 94; an element of the actinide series.

Plutonium was discovered in 1940–41 by the American scientists G. Seaborg, E. McMillan, J. Kennedy, and A. Wahl, who obtained the isotope 238 Pu as a result of irradiation of uranium by nuclei of heavy hydrogen (deuterons). The new element was named for the planet Pluto, as the precursors of plutonium in the Mendeleev table, uranium and neptunium, were named for the planets Uranus and Neptune. Isotopes of plutonium with mass numbers from 232 to 246 are known. Traces of the isotopes 247 Pu and 255 Pu were discovered in dust collected after explosions of thermonuclear bombs. The longest-lived isotope of plutonium is the α-radioactive 244 Pu, which has a half-life of about 7.5 × 107 yr. The half-lives of all the isotopes of plutonium are much less than the age of the earth, and therefore all the primary plutonium that existed on the planet at the time of its formation has completely decayed.

However, extremely small amounts of 239 Pu are continuously formed during -β–decay of 239 Np, which in turn is formed in the nuclear reaction of uranium with neutrons, such as the neutrons of cosmic rays. Thus, traces of plutonium are found in uranium ores. Plutonium is a shiny white metal that exists in six allotropic modifications at temperatures from room temperature to 640°C (its melting point). The allotropie transitions of plutonium are accompanied by discontinuous changes in its density (see Figure 1). A unique feature of metallic plutonium is that it contracts upon heating from 310° to 480°C, rather than expanding, as do other metals. Figure 1. Change in density of metallic plutonium upon heating The configuration of the three outer electron shells of the plutonium atom is 5s25p65d105f66s26p27s2. The chemical properties of plutonium are very similar to those of its precursors in the periodic system, uranium and neptunium. Plutonium forms compounds with oxidation states from + 2 to +7.

The oxides PuO, Pu2O3, and PuO2 and a phase of mixed composition, Pu2O3—Pu4O7, are known. In its compounds with halogens, plutonium usually has an oxidation state of +3, although the halides PuF4, PuF6, and PuCl4 are also known. In solutions, plutonium exists in the forms Pu3+, Pu4+, PuO2 + (plutonoyl ion), PuO 22+ (plutonyl ion), and PuO53–, which correspond to oxidation states from + 3 to +7. These ions, with the exception of PuO53–, may be in solution simultaneously in equilibrium. Ions of plutonium of all oxidation states have a tendency toward hydrolysis and complexing. Of all the isotopes of plutonium, the most important is the α-radioactive 239 Pu, with a half-life of 2.4 × 104 yr.

The nuclei of 239 Pu are capable of fission by chain reaction under the action of neutrons, and therefore 239 Pu may be used as a source of atomic energy (the energy released by the disintegration of 1 g of 239 Pu is equivalent to the heat released upon combustion of 4,000 kg of coal). In the USSR, the first attempts to produce 239 Pu began in 1943–44 under the direction of Academicians I. V. Kurchatov and V. G. Khlopin. Plutonium was first isolated in the USSR in 1945 from a sample of uranium under neutron bombardment. In a very short time, extensive studies of the properties of plutonium were carried out, and in 1949 the first plant for the radiochemical separation of plutonium began operation in the USSR. The industrial production of 239 Pu is based on the reaction of nuclei of 238U with neutrons in nuclear reactors.

The subsequent separation of plutonium from uranium, neptunium, and highly radioactive fission products is carried out by radiochemical methods, such as coprecipitation, extraction, and ion exchange. Metallic plutonium is usually produced by reduction of PuF3, PuF4, or PuO2 by vapors of barium, calcium, or lithium. The isotope 239Pu is used as a fissionable material in atomic reactors and in atomic and thermonuclear bombs. The isotope 238Pu is used for the production of atomic batteries with a service life of 5 yr or more. Such batteries may be used, for example, in current generators for cardiac pacemakers. REFERENCES Bagley, K. Plutonii i ego splavy. Moscow, 1958. (Translated from English.) Vdovenko, V. M., and B. V. Kurchatov. “Pervyi sovetskii plutonii.” Radiokhimiia, 1968, vol. 10, fasc. 6, p. 696. Plutonii: Spravochnik, vols. 1–2. Edited by O.

Wick. Moscow, 1971–73. (Translated from English.) See also references under Chemistry/Plutonium term paper 2166 Chemistry/Plutonium term paper 2166 Chemistry term papers Disclaimer: Free essays on Chemistry posted on this site were donated by anonymous users and are provided for informational use only. The free Chemistry research paper (Plutonium essay) presented on this page should not be viewed as a sample of our on-line writing service . If you need fresh and competent research / writing on Chemistry, use the professional writing service offered by our company. View / hide essay Plutonium Plutonium, symbol Pu, is a radioactive metallic element. It has an atomic number of 94, and it is used in nuclear reactors and weapons. The element is one of the transuranium elements in the actinide series of the periodic table. Isotopes of plutonium were first prepared and studied by the American chemist Glenn T. Seaborg and his associates at the University of California at Berkeley in 1941. Trace amounts of the element have since been found in uranium ores, but plutonium is prepared in relatively large quantities today in nuclear reactors.

Chemically, plutonium is reactive, its properties somewhat resembling those of the rare earth elements. The silvery metal, which becomes slightly yellow through oxidation caused by exposure to air, exists in six varying crystalline forms and has four different oxidation states. The metal gives off heat because of its radioactivity; 15 different isotopes of plutonium, ranging in mass number from 232 to 246, are known. Plutonium melts at about 641ÃâÃÂ° C (about 1186ÃâÃÂ° F), boils at about 3232ÃâÃÂ° C (about 5850ÃâÃÂ° F), and has a specific gravity of 19.84. The most important isotope, plutonium-239, has a half-life of 24,360 years, and is produced by bombarding uranium-238 with slow neutrons. This forms neptunium-239, which in turn emits a beta particle and forms plutonium-239.

Plutonium is the most economically important of the transuranium elements because plutonium-239 readily undergoes fission and can be both used and produced in quantity in nuclear reactors. It is also used in making nuclear weapons. It is an extremely hazardous poison due to its high radioactivity. Plutonium-238 has been used to power equipment on the moon by means of the heat it emits. If plutonium did not exist, I don't think it would have much effect on the world. It would reduce the amount of nuclear weapons and nuclear reactors used, but scientists would just use other radioactive elements. If anything it would make our lifes better, basically because it lessens the chance of atomic explosions. Essays, term papers, research papers (related): Element 94 - definition of Element 94 by The Free Dictionary Element 94 - definition of Element 94 by The Free Dictionary (plo͞o-tō′nē-əm) n. Symbol Pu A radioactive, silvery, metallic transuranic element, occurring in uranium ores and produced artificially by neutron bombardment of uranium. Its longest-lived isotope is Pu-244 with a half-life of 80 million years.

It is a radiological poison, specifically absorbed by bone marrow, and is used, especially the highly fissionable isotope Pu-239, as a reactor fuel and in nuclear weapons. Atomic number 94; melting point 640°C; boiling point 3,228°C; specific gravity 19.84 (25°C); valence 3, 4, 5, 6. See Periodic Table . [After the dwarf planet Pluto (from the fact that it follows neptunium in the periodic table).] plutonium (pluːˈtəʊnɪəm) n (Elements & Compounds) a highly toxic metallic transuranic element. It occurs in trace amounts in uranium ores and is produced in a nuclear reactor by neutron bombardment of uranium-238. The most stable and important isotope, plutonium-239, readily undergoes fission and is used as a reactor fuel in nuclear power stations and in nuclear weapons.

Symbol: Pu; atomic no: 94; half-life of 239Pu: 24 360 years; valency: 3, 4, 5, or 6; relative density (alpha modification): 19.84; melting pt: 640°C; boiling pt: 3230°C [C20: named after the dwarf planet Pluto because Pluto lies beyond Neptune and plutonium was discovered soon after neptunium] plu•to•ni•um (pluˈtoʊ ni əm) n. a radioactive metallic transuranic element with a fissile isotope of mass number 239 that can be produced from nonfissile uranium 238. Symbol: Pu; at. no.: 94. [1940–45; < Greek Ploútōn Pluto + -ium 2] plu·to·ni·um (plo͞o-tō′nē-əm) Symbol Pu A silvery, radioactive metallic element of the actinide series that has the highest atomic number of all naturally occurring elements.

It can be found in minute amounts in uranium ores and is produced artificially by bombarding uranium with neutrons. It is absorbed by bone marrow and is highly poisonous. Plutonium is used in nuclear weapons and as a fuel in nuclear reactors. Its most stable isotope has a half-life of 76 million years. Atomic number 94. See Periodic Table . plutonium Element produced in large quantities by nuclear reactors; also used in nuclear weapons. ThesaurusAntonymsRelated WordsSynonymsLegend: - PLUTONIUM / URANIUM URANIUM - a heavy toxic silvery-white radioactive metallic element; occurs in many isotopes; used for nuclear fuels and nuclear weapons PLUTONIUM 238 - has a half-life of 88 years and emits alpha particles. It is a heat source in radioisotope thermoelectric generators, which are used to power some spacecraft. PLUTONIUM 240 - has a high rate of spontaneous fission, raising the neutron flux of any sample it is in. The presence of plutonium-240 limits a sample's usability for weapons or reactor fuel, and determines its grade.

Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-white appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen and silicon. When exposed to moist air, it forms oxides and hydrides that expand the sample up to 70% in volume, which in turn flake off as a powder that can spontaneously ignite. It is also a radioactive poison that accumulates in bone marrow. These and other properties make the handling of plutonium dangerous. Plutonium (Pu) - definition of Plutonium (Pu) by The Free Dictionary Plutonium (Pu) - definition of Plutonium (Pu) by The Free Dictionary (plo͞o-tō′nē-əm) n. Symbol Pu A radioactive, silvery, metallic transuranic element, occurring in uranium ores and produced artificially by neutron bombardment of uranium. Its longest-lived isotope is Pu-244 with a half-life of 80 million years.

It is a radiological poison, specifically absorbed by bone marrow, and is used, especially the highly fissionable isotope Pu-239, as a reactor fuel and in nuclear weapons. Atomic number 94; melting point 640°C; boiling point 3,228°C; specific gravity 19.84 (25°C); valence 3, 4, 5, 6. See Periodic Table . [After the dwarf planet Pluto (from the fact that it follows neptunium in the periodic table).] plutonium (pluːˈtəʊnɪəm) n (Elements & Compounds) a highly toxic metallic transuranic element. It occurs in trace amounts in uranium ores and is produced in a nuclear reactor by neutron bombardment of uranium-238. The most stable and important isotope, plutonium-239, readily undergoes fission and is used as a reactor fuel in nuclear power stations and in nuclear weapons.

Symbol: Pu; atomic no: 94; half-life of 239Pu: 24 360 years; valency: 3, 4, 5, or 6; relative density (alpha modification): 19.84; melting pt: 640°C; boiling pt: 3230°C [C20: named after the dwarf planet Pluto because Pluto lies beyond Neptune and plutonium was discovered soon after neptunium] plu•to•ni•um (pluˈtoʊ ni əm) n. a radioactive metallic transuranic element with a fissile isotope of mass number 239 that can be produced from nonfissile uranium 238. Symbol: Pu; at. no.: 94. [1940–45; < Greek Ploútōn Pluto + -ium 2] plu·to·ni·um (plo͞o-tō′nē-əm) Symbol Pu A silvery, radioactive metallic element of the actinide series that has the highest atomic number of all naturally occurring elements.

It can be found in minute amounts in uranium ores and is produced artificially by bombarding uranium with neutrons. It is absorbed by bone marrow and is highly poisonous. Plutonium is used in nuclear weapons and as a fuel in nuclear reactors. Its most stable isotope has a half-life of 76 million years. Atomic number 94. See Periodic Table . plutonium Element produced in large quantities by nuclear reactors; also used in nuclear weapons. ThesaurusAntonymsRelated WordsSynonymsLegend: Plutonium | Article about plutonium by The Free Dictionary Plutonium | Article about plutonium by The Free Dictionary Related to plutonium: plutonium 239 plutonium (plo͞otō`nēəm), radioactive chemical element; symbol Pu; at. no. 94; mass no. of most stable isotope 244; m.p. 641&degC;; b.p. 3,232&degC;; sp. gr. 19.84 at 20&degC;; valence +3, +4, +5, or +6.

Plutonium is a silver-gray radioactive metal that has six allotropic forms (see allotropy allotropy [Gr.,=other form]. A chemical element is said to exhibit allotropy when it occurs in two or more forms in the same physical state; the forms are called allotropes. ..... Click the link for more information. ). It is a member of the actinide series actinide series, a series of radioactive metallic elements in Group 3 of the periodic table. Members of the series are often called actinides, although actinium (at. no. 89) is not always considered a member of the series. ..... Click the link for more information. in Group 3 of the periodic table periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled ..... Click the link for more information. . Plutonium is chemically reactive. It tarnishes in air, taking on a yellow cast when oxidized.

It dissolves in hydrochloric, hydriodic, and perchloric acids and reacts with the halogens, carbon, nitrogen, and silicon. Pure plutonium metal may be prepared by reduction of the trifluoride, PuF3, with calcium metal. Sixteen isotopes of plutonium are known. The most stable is plutonium-244 (half-life about 82 million years). By far the most important is plutonium-239 (half-life about 24,000 years), a nuclear fission fuel. Plutonium-239 is produced in large quantities in nuclear reactors from uranium-238, an abundant but nonfissionable isotope. Uranium-238 absorbs neutrons emitted by the fission of uranium-235; uranium-239 is formed, which emits a beta particle and decays to neptunium-239; the neptunium-239 emits another beta particle, becoming plutonium-239. Once begun, the reaction proceeds spontaneously until the uranium fuel rods in the reactor are converted to a certain uranium-plutonium mixture.

The rods are dissolved in acid and the plutonium separated by chemical means, especially by solvent extraction. Plutonium is important for its use in nuclear weapons and nuclear reactors. Plutonium-238 has been used to power scientific equipment in lunar exploration and implanted heart pacemakers (see pacemaker, artificial pacemaker, artificial, device used to stimulate a rhythmic heartbeat by means of electrical impulses. Implanted in the body when the heart's own electrical conduction system (natural pacemaker) does not function normally, the battery-powered device emits impulses that trigger ..... Click the link for more information. ). Plutonium is an extremely dangerous poison; it collects in the bones and interferes with the production of white blood cells. Plutonium is found naturally in very small quantities in association with uranium ores. However, it was discovered in 1940 at the Univ. of California at Berkeley by Glenn T. Seaborg Seaborg, Glenn Theodore , 1912–99, American chemist, b. Ishpeming, Mich., grad. Univ. of California at Los Angeles, 1934, Ph.D. Univ. of California at Berkeley, 1937. .....

Click the link for more information. , Edwin M. McMillan McMillan, Edwin Mattison, 1907–91, American physicist, b. Redondo Beach, Calif., grad. California Institute of Technology, 1928, Ph.D. Princeton, 1932. On the faculty of the Univ. ..... Click the link for more information. , Joseph W. Kennedy, and Arthur C. Wahl; using a cyclotron to bombard uranium oxide with deuterons, they produced plutonium-238 ( half-life half-life, measure of the average lifetime of a radioactive substance (see radioactivity) or an unstable subatomic particle. One half-life is the time required for one half of any given quantity of the substance to decay. ..... Click the link for more information. about 87 years). Plutonium, the second transuranium element transuranium elements, in chemistry, radioactive elements with atomic numbers greater than that of uranium (at. no. 92). All the transuranium elements of the actinide series were discovered as synthetic radioactive isotopes at the Univ. ..... Click the link for more information.

, was named for Pluto Pluto, in astronomy, a dwarf planet and the first Kuiper belt, or transneptunian, object (see comet) to be discovered (1930) by astronomers. Pluto has an elliptical orbit usually lying beyond that of Neptune. ..... Click the link for more information. , then regarded as the second planet beyond Uranus. Plutonium Pu, an artificial radioactive chemical element with atomic number 94; an element of the actinide series. Plutonium was discovered in 1940–41 by the American scientists G. Seaborg, E. McMillan, J. Kennedy, and A. Wahl, who obtained the isotope 238 Pu as a result of irradiation of uranium by nuclei of heavy hydrogen (deuterons). The new element was named for the planet Pluto, as the precursors of plutonium in the Mendeleev table, uranium and neptunium, were named for the planets Uranus and Neptune. Isotopes of plutonium with mass numbers from 232 to 246 are known.

Traces of the isotopes 247 Pu and 255 Pu were discovered in dust collected after explosions of thermonuclear bombs. The longest-lived isotope of plutonium is the α-radioactive 244 Pu, which has a half-life of about 7.5 × 107 yr. The half-lives of all the isotopes of plutonium are much less than the age of the earth, and therefore all the primary plutonium that existed on the planet at the time of its formation has completely decayed. However, extremely small amounts of 239 Pu are continuously formed during -β–decay of 239 Np, which in turn is formed in the nuclear reaction of uranium with neutrons, such as the neutrons of cosmic rays. Thus, traces of plutonium are found in uranium ores. Plutonium is a shiny white metal that exists in six allotropic modifications at temperatures from room temperature to 640°C (its melting point). The allotropie transitions of plutonium are accompanied by discontinuous changes in its density (see Figure 1).

A unique feature of metallic plutonium is that it contracts upon heating from 310° to 480°C, rather than expanding, as do other metals. Figure 1. Change in density of metallic plutonium upon heating The configuration of the three outer electron shells of the plutonium atom is 5s25p65d105f66s26p27s2. The chemical properties of plutonium are very similar to those of its precursors in the periodic system, uranium and neptunium. Plutonium forms compounds with oxidation states from + 2 to +7. The oxides PuO, Pu2O3, and PuO2 and a phase of mixed composition, Pu2O3—Pu4O7, are known. In its compounds with halogens, plutonium usually has an oxidation state of +3, although the halides PuF4, PuF6, and PuCl4 are also known.

In solutions, plutonium exists in the forms Pu3+, Pu4+, PuO2 + (plutonoyl ion), PuO 22+ (plutonyl ion), and PuO53–, which correspond to oxidation states from + 3 to +7. These ions, with the exception of PuO53–, may be in solution simultaneously in equilibrium. Ions of plutonium of all oxidation states have a tendency toward hydrolysis and complexing. Of all the isotopes of plutonium, the most important is the α-radioactive 239 Pu, with a half-life of 2.4 × 104 yr. The nuclei of 239 Pu are capable of fission by chain reaction under the action of neutrons, and therefore 239 Pu may be used as a source of atomic energy (the energy released by the disintegration of 1 g of 239 Pu is equivalent to the heat released upon combustion of 4,000 kg of coal). In the USSR, the first attempts to produce 239 Pu began in 1943–44 under the direction of Academicians I. V.

Kurchatov and V. G. Khlopin. Plutonium was first isolated in the USSR in 1945 from a sample of uranium under neutron bombardment. In a very short time, extensive studies of the properties of plutonium were carried out, and in 1949 the first plant for the radiochemical separation of plutonium began operation in the USSR. The industrial production of 239 Pu is based on the reaction of nuclei of 238U with neutrons in nuclear reactors. The subsequent separation of plutonium from uranium, neptunium, and highly radioactive fission products is carried out by radiochemical methods, such as coprecipitation, extraction, and ion exchange. Metallic plutonium is usually produced by reduction of PuF3, PuF4, or PuO2 by vapors of barium, calcium, or lithium. The isotope 239Pu is used as a fissionable material in atomic reactors and in atomic and thermonuclear bombs. The isotope 238Pu is used for the production of atomic batteries with a service life of 5 yr or more.

Such batteries may be used, for example, in current generators for cardiac pacemakers. REFERENCES Bagley, K. Plutonii i ego splavy. Moscow, 1958. (Translated from English.) Vdovenko, V. M., and B. V. Kurchatov. “Pervyi sovetskii plutonii.” Radiokhimiia, 1968, vol. 10, fasc. 6, p. 696. Plutonii: Spravochnik, vols. 1–2. Edited by O. Wick. Moscow, 1971–73. (Translated from English.) See also references under Plutonium | Define Plutonium at Dictionary.com plutonium [ploo-toh-nee-uh m] /pluˈtoʊ ni əm/ Spell noun, Chemistry, Physics. 1. a transuranic element with a fissile isotope of mass number 239 (plutonium 239) that can be produced from non-fissile uranium 238, as in a breeder reactor. Symbol: Pu; atomic number: 94.

Origin of plutonium 1940-45; < Greek Ploútōn Pluto + -ium Dictionary.com Unabridged Examples from the Web for plutonium Expand Contemporary Examples Possibly as triumphant as ending World War II with a bomb made from plutonium developed here. Yes, Your Toddler Can Watch TV: The New Rules for Screen Time Russell Saunders December 25, 2014 In that time, we might give up our plutonium reprocessing plant but retain our newer uranium enrichment facilities. The Cosmic Computer Henry Beam Piper Los Alamos scientists devised two designs for an atomic bomb--one using the uranium and another using the plutonium. Trinity [Atomic test] Site White Sands Missile Range Public Affairs Office I wonder if he has any idea of what else plutonium can be used for? Ullr Uprising Henry Beam Piper After letting the temperatures of the plutonium and casing equalize the core slid smoothly into place. Trinity [Atomic test] Site White Sands Missile Range Public Affairs Office British Dictionary definitions for plutonium Expand noun 1. a highly toxic metallic transuranic element. It occurs in trace amounts in uranium ores and is produced in a nuclear reactor by neutron bombardment of uranium-238.

The most stable and important isotope, plutonium-239, readily undergoes fission and is used as a reactor fuel in nuclear power stations and in nuclear weapons. Symbol: Pu; atomic no: 94; half-life of 239Pu: 24 360 years; valency: 3, 4, 5, or 6; relative density (alpha modification): 19.84; melting pt: 640°C; boiling pt: 3230°C Word Origin C20: named after the dwarf planet Pluto because Pluto lies beyond Neptune and plutonium was discovered soon after neptunium Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Word Origin and History for plutonium Expand n.

transuranic element, 1942, from Pluto , the planet, + element ending -ium. Discovered at University of California, Berkeley, in 1941, the element named on suggestion of Seaborg and Wahl because it follows neptunium in the periodic table as Pluto follows Neptune in the Solar System. The name plutonium earlier had been proposed for barium and was sometimes used in this sense early 19c. Online Etymology Dictionary, © 2010 Douglas Harper -tō'nē-əm) Symbol Pu A silvery, radioactive metallic element of the actinide series that has the highest atomic number of all naturally occurring elements. It is found in minute amounts in uranium ores and is produced artificially by bombarding uranium with neutrons. It is absorbed by bone marrow and is highly poisonous. Plutonium is used in nuclear weapons and as a fuel in nuclear reactors. Its longest-lived isotope is Pu 244 with a half-life of 76 million years.

Atomic number 94; melting point 640°C; boiling point 3,232°C; specific gravity 19.84; valence 3, 4, 5, 6. See Periodic Table . The American Heritage® Science Dictionary Copyright © 2002. Published by Houghton Mifflin. All rights reserved. Plutonium - Credo Reference Topic Page: Plutonium Definition: plutonium from Dictionary of Energy Chemistry. a metallic element with the symbol Pu, the atomic number 94, an atomic weight (for its most stable isotope) of 244, a melting point of 640°C, and a boiling point of 3230°C; it occurs as fifteen radioactive isotopes (having mass numbers from 232 to 246) and in six allotropic forms. Plutonium and all elements of higher atomic number are radiological poisons because of their high rate of alpha emission and their specific absorption in bone marrow. Summary Article: plutonium from The Columbia Encyclopedia Image from: nuclear power station in The Hutchinson Encyclopedia (plutō'nēəm), radioactive chemical element; symbol Pu; at. no.

94; mass no. of most stable isotope 244; m.p. 641 degrees Celsius; b.p. 3,232 degrees Celsius; sp. gr. 19.84 at 20 degrees Celsius; valence +3, +4, +5, or +6. Plutonium is a silver-gray radioactive metal that has six allotropic forms (see allotropy). It is a member of the actinide series in Group 3 of the periodic table. Plutonium is chemically reactive. It tarnishes in air, taking on a yellow cast when oxidized. It dissolves in hydrochloric, hydriodic, and perchloric acids and reacts with the halogens, carbon, nitrogen, and silicon. Pure plutonium metal may be prepared by reduction of the trifluoride, PuF3, with calcium metal. Sixteen isotopes of plutonium are known. The most stable is plutonium-244 (half-life about 82 million years). By far the most important is plutonium-239 (half-life about 24,000 years), a nuclear fission fuel.

Plutonium-239 is produced in large quantities in nuclear reactors from uranium-238, an abundant but nonfissionable isotope. Uranium-238 absorbs neutrons emitted by the fission of uranium-235; uranium-239 is formed, which emits a beta particle and decays to neptunium-239; the neptunium-239 emits another beta particle, becoming plutonium-239. Once begun, the reaction proceeds spontaneously until the uranium fuel rods in the reactor are converted to a certain uranium-plutonium mixture. The rods are dissolved in acid and the plutonium separated by chemical means, especially by solvent extraction. Plutonium is important for its use in nuclear weapons and nuclear reactors. Plutonium-238 has been used to power scientific equipment in lunar exploration and implanted heart pacemakers (see pacemaker, artificial). Plutonium is an extremely dangerous poison; it collects in the bones and interferes with the production of white blood cells. Plutonium is found naturally in very small quantities in association with uranium ores. However, it was discovered in 1940 at the Univ.

of California at Berkeley by Glenn T. Seaborg, Edwin M. McMillan, Joseph W. Kennedy, and Arthur C. Wahl; using a cyclotron to bombard uranium oxide with deuterons, they produced plutonium-238 (half-life about 87 years). Plutonium, the second transuranium element, was named for Pluto, then regarded as the second planet beyond Uranus. The Columbia Encyclopedia, © Columbia University Press 2016 Plutonium Plutonium Plutonium, symbol Pu, is a radioactive metallic element. It has an atomic number of 94, and it is used in nuclear reactors and weapons. The element is one of ... Plutonium Plutonium, symbol Pu, is a radioactive metallic element. It has an atomic number of 94, and it is used in nuclear reactors and weapons. The element is one of the transuranium elements in the actinide series of the periodic table. Isotopes of plutonium were first prepared and studied by the American chemist Glenn T. Seaborg and his associates at the University of California at Berkeley in 1941.

Trace amounts of the element have since been found in Plutonium An American Chemist named Glenn T. Seaborg discovered plutonium in 1941 at Berkeley University in California. The discovery of Plutonium was not announced until 1946 because America was at war ... uranium ores, but plutonium is prepared in relatively large quantities today in nuclear reactors. Chemically, plutonium is reactive, its properties somewhat resembling those of the rare earth elements. The silvery metal, which becomes slightly yellow through oxidation caused by exposure to air, exists in six varying crystalline forms and has four different oxidation states. The metal gives off heat because of its radioactivity ;15 different isotopes of plutonium, ranging in mass number from 232 to 246, are known. Plutonium melts Plutonium Plutonium Plutonium is a radioactive metallic element. Although it is occasionally found in nature, mostly all of our plutonium is produced artificially in a lab. The official chemical symbol ...

at about 641ï¿½ C (about 1186ï¿½ F), boils at about 3232ï¿½ C (about 5850ï¿½ F), and has a specific gravity of 19.84. The most important isotope, plutonium-239, has a half-life of 24,360 years, and is produced by bombarding uranium-238 with slow neutrons. This forms neptunium-239, which in turn emits a beta particle and forms plutonium-239. Plutonium is the most economically important of the transuranium elements because plutonium-239 readily undergoes fission and can be both used and produced in quantity in

Question: Which radioactive metallic element has the symbol Pu, atomic number 94?
Answer: Plutonium